title: Differential regulatory T cell activity in HIV type 1-exposed seronegative individuals.
abstract: The potential role of conventional and regulatory T cells (Tregs) in protection from HIV-1 infection remains unclear. To address this question, we analyzed samples from 129 HIV-1-exposed seronegative individuals (HESN) from an HIV-1-serodiscordant couples cohort. To assess the presence of HIV-specific T cell responses and Treg function, we measured the proliferation of T cells in response to HIV-1 peptide pools in peripheral blood mononuclear cells (PBMCs) and PBMCs depleted of Tregs. We identified HIV-specific CD4(+) and CD8(+) T cell responses and, surprisingly, the overall CD4(+) and CD8(+) T cell response rate was not increased when Tregs were removed from cell preparations. Of the 20 individuals that had HIV-1-specific CD4(+) T cell responses, only eight had Tregs that could suppress this proliferation. When compared with individuals whose Tregs could suppress HIV-1-specific CD4(+) T cell proliferation, individuals with Tregs unable to suppress showed a trend toward increased T cell activation and Treg frequency and a significant increase in HIV-1-specific production of microphage inflammatory protein-1β (MIP-1β) by CD4(+) T cells, autocrine production of which has been shown to be protective in terms of HIV-1 infection of CD4(+) T cells.
authors.affiliation: 1 Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center , Seattle, Washington.
authors.forename: Laura
authors.initials: L
authors.lastname: Pattacini
authors.forename: Pamela M
authors.initials: PM
authors.lastname: Murnane
authors.forename: Erin M
authors.initials: EM
authors.lastname: Kahle
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Bolton
authors.forename: Jeffrey J
authors.initials: JJ
authors.lastname: Delrow
authors.forename: Jairam R
authors.initials: JR
authors.lastname: Lingappa
authors.forename: Elly
authors.initials: E
authors.lastname: Katabira
authors.forename: Deborah
authors.initials: D
authors.lastname: Donnell
authors.forename: M Juliana
authors.initials: MJ
authors.lastname: McElrath
authors.forename: Jared M
authors.initials: JM
authors.lastname: Baeten
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Lund
mesh_terms: D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D049109:Cell Proliferation; D054407:Chemokine CCL4 / Q000378:metabolism; D005260:Female; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008297:Male; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*
chemical_list: C066507:CCL4 protein, human; D054407:Chemokine CCL4